Peristaltic hose pumps are, for instance, used as suction and rinse pumps for medical purposes, in particular in minimal-invasive surgery. Specific applications include arthroscopy, laparoscopy, urology, hysteroscopy and cystoscopy. For medical applications, in particular a sterility meeting all requirements is needed, and for this reason, after use, the hose cartridge is usually disposed of, in order to avoid cross contamination between different patients. Therefore, the hose cartridges have to be low-priced, and, in particular, permit simple handling by operators, when the hose cartridge is connected with the pump as well as when it is removed therefrom.
For prior art peristaltic pumps, there are in principle two different basic concepts. The first basic concept is that the hose arranged around the roller wheel is pressed by means of a pressure bracket or the like against the roller wheel. Such peristaltic hose pumps systems are for instance known from the documents U.S. Pat. No. 4,798,580, U.S. Pat. No. 5,044,902, U.S. Pat. No. 5,213,483 and DE 100 62 600.9 A1. By a closure lever mechanism, the hose is fixed and pressed against the roller wheel by means of a pressure bracket.
The second basic concept, which the invention in principle uses, is that the hose is drawn around the roller wheel with a sufficient encircling angle by a traction of a suitable size. Thereby, a pressure bracket or the like is not required. The traction has to be selected, in consideration of the elastic properties of the hose, such that in the area of a roller of a roller wheel, the inner cross section of the hose is practically reduced to zero. With regard thereto, it is for instance known from the document DE 199 60 668 C1 that in a hose cartridges at least one leg of the pump hose segment following the circular segment is arranged displaceably in the longitudinal direction of the hose in the cartridge housing between a mounting position and an operating position. This is in principle very well established, yet requires a relatively complicated construction and is thus expensive to manufacture.
A hose cartridge of the construction mentioned above is known from the document U.S. Pat. No. 4,537,561. Therein, a straight pump hose segment is provided in a hose cartridge. The hose cartridge is inserted at right angles to the extension of the pump hose segment into the peristaltic pump, and the pump hose segment comes into contact with the roller wheel and is tensioned, during the insertion of the hose cartridge, with a low encircling angle around the roller wheel. In the insofar known hose cartridges, it is a disadvantage that, due to the geometry of the components, a sufficient pressure on the pump hose segment by the roller wheel is only achieved with relatively high forces. On the one hand, this requires high forces for the insertion of the hose cartridge, while on the other hand, components of the hose cartridge are subjected to bending moments, thus requiring a relatively stable structure.